Seasonal Stability Tests in gretl. An Application to International Tourism Data

The seasonal stability tests of Canova & Hansen (1995) (CH) provide a method complementary to that of Hylleberg et al. (1990) for testing for seasonal unit roots. But the distribution of the CH tests are unknown in small samples. We present a method to numerically compute critical values and P-values for the CH tests for any sample size and any seasonal periodicity. In fact this method is applicable to the types of seasonality which are commonly in use, but also to any other.

Parylene-C as a new piezoelectric material

The goal of this thesis is to develop a proper microelectromechanical systems (MEMS) process to manufacture piezoelectric Parylene-C (PA-C), which is famous for its chemical inertness, mechanical and thermal properties and electrical insulation. Furthermore, piezoelectric PA-C is used to build miniature, inexpensive, non-biased piezoelectric microphones.

These piezoelectric PA-C MEMS microphones are to be used in any application where a conventional piezoelectric and electret microphone can be used, such as in cell phones and hearing aids. However, they have the advantage of a simplified fabrication process compared with existing technology. In addition, as a piezoelectric polymer, PA-C has varieties of applications due to its low dielectric constant, low elastic stiffness, low density, high voltage sensitivity, high temperature stability and low acoustic and mechanical impedance. Furthermore, PA-C is an FDA approved biocompatible material and is able to maintain operate at a high temperature.

To accomplish piezoelectric PA-C, a MEMS-compatible poling technology has been developed. The PA-C film is poled by applying electrical field during heating. The piezoelectric coefficient, -3.75pC/N, is obtained without film stretching.

The millimeter-scale piezoelectric PA-C microphone is fabricated with an in-plane spiral arrangement of two electrodes. The dynamic range is from less than 30 dB to above 110 dB SPL (referenced 20 µPa) and the open-circuit sensitivities are from 0.001 – 0.11 mV/Pa over a frequency range of 1 - 10 kHz. The total harmonic distortion of the device is less than 20% at 110 dB SPL and 1 kHz.

GitLine tresnaren zabaltzea: software produktu-lerroen kudeaketa

Gradu amaierako proiektu hau software produktu-lerroen testuinguruan kokatzen da, GitLine aplikazioan funtzionalitate batzuk gehituz. GitLine, Onekin ikerketa taldean [13] garatua, GitHub-en funtzionalitate gehigarriak eskaintzen dituen Firefox-eko plugin bat da. Plugin honek SPL produktu eraikitzaileari laguntza eskaintzen dio ezaugarri biltegiak eta produktu biltegiak sortu eta beraien arteko sinkronizazioa mantentzeko. Sinkronizazio hori hobetzeko, ikasleak hiru funtzionalitate berri inplementatu ditu. GitLine-en inplementatuta dagoen productFork funtzionalitateari, hau da, ezaugarri biltegi batetik aukeratutako ezaugarriekin produktu biltegia sortzeko funtzionalitateari, hobekuntza nabarmen bat gehitu dio ikasleak: baliozkoak diren produktu biltegiak bakarrik sortzen direla ziurtatzen du (balioztaketa). Hobekuntza honi esker, produktu biltegiak erabat sinkronizatuta daude ezaugarri biltegiarekin. Ezaugarri biltegi baten bizi-zikloa handitzeko, ikasleak ezaugarri biltegian ezaugarri berriak txertatzeko aukera inplementatu du (ezaugarria txertatu). Gainera, hasieran aipatutako ezaugarri biltegi eta produktu biltegien arteko sinkronizazio hori bermatzeko, ezaugarri berriak txertatzerakoan, ezaugarri berri horiek sortuta dauden produktu biltegietara hedatzeko aukera inplementatu du ere (ezaugarria hedatu).

Prediction of sound emission from open turbulent premixed flames

The sound emission from open turbulent flames is dictated by the two-point spatial correlation of rate of change of fluctuating heat release rate and this correlation has not been investigated directly in the past studies. Turbulent premixed flame data from DNS and laser diagnostics are analyzed to study this correlation function and the two-point spatial correlation of the fluctuating heat release rate. This shows that the correlation functions have simple Gaussian forms whose integral length scale is related to the laminar flame thickness and amplitude depends on the spatial distribution of the time-mean rate of heat release. These results and RANS-CFD solution of open turbulent premixed flames are post-processed to obtain the far field SPL, which agrees well with measured values. © 2010 by the American Institute of Aeronautics and Astronautics, Inc.

The genetic diversity of Acipenser stellatus populations in the Caspian Sea was studied using microsatellite technique

A total of 361 caudal fin samples were collected from adult A. stellatus specimens caught in the north Caspian Sea, including specimens from Kazakhstan (Ural River), Russia (Volga River), Azerbaijan (Kura River), specimens caught in the south Caspian Sea including specimens from Fishery Zone 1 (from Astara to Anzali), Fishery Zone 2 (from Anzali to Ramsar), Fishery Zone 3 (from Nowshahr to Babolsar), Fishery Zone 4 (from Miyankaleh to Gomishan) as well as from specimens caught in Turkmenistan (all specimens were collected during the sturgeon stock assessment survey). About 2 g of fin tissue was removed from each caudal fin sample, stored in 96% ethyl alcohol and transferred to the genetic laboratory of the International Sturgeon Research Institute. Genomic DNA was extracted using phenol-chloroform method. The quality and quantity of DNA was assessed using 1% Agarose gel electrophoresis and Polymerase Chain Reaction (PCR) was conducted on the target DNA using 15 paired microsatellite primer. PCR products were electrophoresed on polyacrylamide gels (6%) that were stained using silver nitrate. Electrophoretic patterns and DNA bands were analyzed with BioCapt software. Allele count and frequency, genetic diversity, expected heterozygosity and observed heterozygosity allele number, and the effective allele number, genetic similarity and genetic distance, FST and RST were calculated. The Hardy Wienberg Equilibrium based on X2 and Analysis of Molecular Variance (AMOVA) at 10% confidence level was calculated using the Gene Alex software. Dendrogram for genetic distances and identities were calculated using TFPGA program for any level of the hierarchy. It is evident from the results obtained that the 15 paired primers studied, polymorphism was observed in 10 pairs in 12 loci, while one locus did not produce DNA bands. Mean allele number was 13.6. Mean observed and expected heterozygosity was 0.86 and 0.642, respectively. It was also seen that specimens from all regions were not in Hardy Wienberg Equilibrium in most of the loci (P≤0.001). Highest Fst (0.063) was observed when comparing specimens from Fishery Zone 2 and Fishery Zone 4 (Nm=3.7) and lowest FST (0.028) was observed when comparing specimens from the Volga River and those from the Ural River (8.7). Significant differences (P<0.01) were observed between RST recorded in the specimens studied. Highest genetic distance (0.604) and lowest genetic resemblance (0.547) were observed between specimens from Fishery zones 2 and 4. Lowest genetic distance (0.311) and highest genetic resemblance (0.733) was observed between specimens from Turkmenistan and specimens from Fishery zone 1. Based on the genetic dendrogeram tree derived by applying UPGMA algorithm, A. stellatus specimens from Fishery zone 2 or in other words specimens from the Sepidrud River belong to one cluster which divides into two clusters, one of which includes specimens from Fishery zones 1, 3 and 4 and specimens from Turkmenistan while the other cluster includes specimens from Ural, Volga and Kura Rivers. It is thus evident that the main population of this species belongs to the Sepidrud River. Results obtained from the present study show that at least eight different populations of A. stellatus are found in the north and south Caspian Sea, four of which are known populations including the Ural River population, the Volga River population, the Kura River population and the Sepidrud River populations. The four other populations identified belonging to Fishery zones 1, 3, and 4 and to Turkmenistan are most probably late or early spawners of the spring run and autumn run of each of the major rivers mentioned. Specific markers were also identified for each of the populations identified. The Ural River population can be identified using primers Spl-68, 54b and Spl-104, 163 170, 173, the Volga River population can be identified using primers LS-54b and Spl-104, 170, 173 113a and similarly the population from the Kura River can be identified using primers LS-34, 54b and Spl-163, 173 and that from the Sepidrud River can be identified using primers LS-19, 34, 54b and Spl-105, 113b. This study gives evidence of the presence of different populations of this species and calls for serious measures to be taken to protect the genetic stocks of these populations. Considering that the population of A. stellatus in Fishery zone 2 is an independent population of the Sepidrud River in the Gilan Province, the catch of these fishes in the region needs to be controlled and regulated in order to restore the declining stocks of this species.

铲鲟微卫星引物对中华鲟的适用性研究

将 2 1对铲鲟 (ScaphirhynchusplatorynchusRafinesque)的微卫星引物在中华鲟 (AcipensersinensisGray)基因组DNA上进行PCR扩增 ,1 4对 (约占 67% )引物得到了扩增产物 ,其中有 1 0对 (约占 48% )表现为多态性 ,但只有 2对 ( 9 5 % )引物Spl 1 0 0和Spl 1 68的多态性较高 ,且带型清晰 ,可直接作为分子标记应用于相关的研究。此外 ,对具有特异性扩增 ,但有Stutterband现象的 4对引物的部分

Acoustic signals of Chinese alligators (Alligator sinensis): Social communication

This paper reports the first systematic study of acoustic signals during social interactions of the Chinese alligator (Alligator sinensis). Sound pressure level (SPL) measurements revealed that Chinese alligators have an elaborate acoustic communication system with both long-distance signal-bellowing-and short-distance signals that include tooting, bubble blowing, hissing, mooing, head slapping and whining. Bellows have high SPL and appear to play an important role in the alligator's long range intercommunion. Sounds characterized by low SPL are short-distance signals used when alligators are in close spatial proximity to one another. The signal spectrographic analysis showed that the acoustic signals of Chinese alligators have a very low dominant frequency, less than 500 Hz. These frequencies are consistent with adaptation to a habitat with high density vegetation. Low dominant frequency sound attenuates less and could therefore cover a larger spatial range by diffraction in a densely vegetated environment relative to a higher dominant frequency sound. (C) 2007 Acoustical Society of America.

Complex mutation at a microsatellite locus in sturgeons: Acipenser sinensis, A-schrenckii, A-gueldenstaedtii and A-baerii

Cross-species amplifications of microsatellite locus Spl-106, which was originally screened from the genome of shovelnose sturgeon (Scaphirhynchus platorynchus) with a perfect TAGA repeat motif, were carried out in four other species of the genera Acipenser. A total of 34 polymerase chain reaction (PCR) products representing 16 different alleles of this locus was sequenced. Sequence analysis results showed that besides the number changes of repeat units, many mutational events, such as single-base substitutions and various insertion/deletion (indels) occurred not only at species level but also at individual level, even among the different alleles within the same individual. The repeat motifs varied from perfect (TAGA)n array to perfect compound (TAAA)m (GAAA)n and perfect or imperfect compound (TAAA)m (TAGA)n (TAAA)x arrays in different species and different individuals. The evolution dynamics of this locus in sturgeons was inferred in that it may evolve from a single perfect to different perfect or imperfect compounds.

A ridge width varied two-section index-coupled DFB self-pulsation laser with a wide continuously tunable frequency range

A 1.55 mu m InGaAsP-InP index-coupled two-section DFB self-pulsation laser (SPL) with a varied ridge width has been fabricated. A record wide self-pulsation tuning range above 450 GHz has been achieved for this index-coupled DFB SPL. Furthermore, frequency locking to an optically injected modulated signal is successfully demonstrated.

All-optical clock recovery using a ridge width varied two-section partly gain-coupled DFB self-pulsation laser

A 1.55 mu m InGaAsP-InP partly gain-coupled two-section DFB self-pulsation laser (SPL) with a varied ridge width has been fabricated. The laser produces self-pulsations with a frequency tuning range of more than 135 GHz. All-optical clock recovery from 40 Gb/s degraded data streams has been demonstrated. Successful lockings of the device at frequencies of 30 GHz, 40 GHz, 50 GHz, and 60 GHz to a 10 GHz sidemode injection are also conducted, which demonstrates the capability of the device for all-optical clock recovery at different frequencies. This flexibility of the device is highly desired for practical uses. Crown Copyright

纳米结构的构建与表征

在纳米尺寸上按照人们意愿排列物质分子、原子以及进行材料和分子的剪裁具有重 要的研究意义。本论文利用扫描探针加工技术构建种类、形状、尺寸等可控的纳米结构，并且结合表面增强拉曼光谱，对其进行了表征。同时，发展了一种合成可控形貌半导纳米结构的溶液方法，观察了在溶剂挥发作用下纳米粒子在固一液界面的白组装，这种白组装现象有望实现自然自聚集纳米器件的合成。并且制备了一种高效拉曼活性基底，稳定性和重复性好。1．探针针尖性能对扫描探针刻蚀（SPL）的影响采用四种不同类型的针尖：标准Si3N4针尖、敲击模式刻蚀Si针尖、俄罗斯针尖（末覆涂层的Si针尖）、导电针尖进行扫描探针刻蚀实验。发现针尖性能是刻蚀过程中一个重要的因素。具有较小弹性常数的针尖不易在基底进行图案刻划和粒子的操纵。并且，给出了才目应的机理。2．利用“纳米笔”加工技术（DPN）直接构建纳米结构 罗丹明6G（R6G）是一种重要的激光染料和生物染料。利用“纳米笔”加工技术在新解 离的云母表面获得了R6G分子排列。R6G分子通过静电作用结合在云母表面，并且形 成稳定的R6G纳米结构。通过控制针尖不同的运动方向，在云母上构建了不同形状的R6G纳米结构。同时讨论了针尖运行速度和接触时间对DPN的影响。结合表面增强拉曼散射效应，对这些构建的纳米结构进行了定性验证。聚-L-赖氨酸是一种常用的表面修饰试剂，它可以增强生物分子或细胞与表面间的吸附力。利用OPN技术成功的在云母表面获得了聚-L-赖氨酸纳米结构。通过控制针尖不同的运动方向，在表面构建了不同形状包括方块、线条、点、十字花等纳米图案。这种局 部或特定区域的修饰表面在生物化学传感器或微、纳米排列的实现上具有重要的潜在应用价值。牛血．清白蛋白和小牛胸腺组蛋白都是非常重要的蛋白质分子。利用DPN技术将这些蛋自质分子成功的沉积在云母表面。同时考察了针尖一基底接触时间及针尖运行速度对OPN 的影响。这种蛋白质纳米结构的构建为生物纳米器件的最终实现提供了一条简单而有效的途径。3．ZnO纳米结构可控合成及其在固一液界面的自组装使用一种简单而温和的方法直接在溶液中合成了不同ZnO纳米结构。通过调节水一甲醇比率，分别获得zno纳米线、纳米棒和纳米粒子。获得的这些ZnO纳米结构用AFM、XPS及荧光光谱加以表征。讨论了水一甲醇比率对合成ZnO纳米结构不同形貌的影响，给出了可能的机理。溶剂挥发作用卜，zno纳米粒子在云母和玻璃表面进行白组装。不同条件卜，获得不同形状的自组装排列图案。结合现有理论，给出了合理解释。这种方法可以引导纳米粒子的排列，有望实现白然自聚集纳米器件的合成。4．表面增强拉曼活性基底制备和表征使用CTAB，利用一种简单的方法制备了SERS活性基底，并且呈现很好的拉曼响应。对于R6G的检测浓度可以达到1*10-14M，且稳定性和重复性好。结合重定位技术，获得了银纳米晶、簇和膜的AFM图像，而且获得了单分子R6G在同一聚集位置上的SERS光谱。讨论了增强因子的影响因素，并且给出了合理的机理。

The influence of tip performance on scanning probe lithography

Scanning probe lithography (SPL), employing the tip of an atomic force microscope to mechanically pattern various materials in nanoscale region has provided a simple but significant method for making nanostructures. We use this technique for the lithography of several kinds of substrate surfaces. The tip performance has been found to be a crucial factor in the lithographic process. Four types of cantilevers are employed in nanolithography, including standard silicon nitride (DNP), tapping mode(TM) etched silicon (TESP(W)), uncoated silicon cantilever (NSC21/50) and conductive platinum/iridium-coated probe. Results demonstrate that tips with smaller spring constants can not be used for physically scribing and nanomanipulating in our experiment. The possible mechanism of our experiment is discussed.

Experimental study on the impact of dinoflagellate Alexandrium species on populations of the rotifer Brachionus plicatilis

To investigate harmful effects of the dinoflagellate Alexandrium species on microzooplankton, the rotifer Brachionus plicatilis was chosen as an assay species, and tested with 10 strains of Alexandrium including one known non-PSP-producer (Alexandrium tamarense, AT-6). HPLC analysis confirmed the PSP-content of the various strains: Alexandrium lusitanicum, Alexandrium minutum and Alexandrium tamarense (ATHK, AT5-1, AT5-3, ATC102, ATC103) used in the experiment were PSP-producers. No PSP toxins were detected in the strains Alexandrium sp1, Alexandrium sp2. Exposing rotifer populations to the densities of 2000 cells ml(-1) of each of these 10 Alexandrium strains revealed that the (non-PSP) A. tarnarense (AT-6) and two other PSP-producing algae: A. lusitanicum, A. minutum, did not appear to adversely impact rotifer populations. Rotifers exposed to these three strains were able to maintain their population numbers, and in some cases, increase them. Although some increases in rotifer population growth following exposures to these three algal species were noted, the rate was less than for the non-exposed control rotifer groups. In contrast, the remaining seven algal strains (A. tamarense ATHK, AT5-1, AT5-3, ATC102, ATC103; also Alexandrium sp1 and Alexandrium sp2) all have adverse effects on the rotifers. Dosing rotifers with respective algal cell densities of 2000 cells ml-1 each, for Alexandrium spl, Alexandrium sp2, and A. tamarense strains ATHK and ATC103 showed mean lethal time (LT50) on rotifer populations of 21, 28, 29, and 36h, respectively. The remaining three species (A. tamarense strains AT5-1, AT5-3, ATC102) caused respective mean rotifer LT50S of 56, 56, and 71 h, compared to 160 h for the unexposed "starved control" rotifers. Experiments to determine ingestion rates for the rotifers, based on changes in their Chlorophyll a content, showed that the rotifers could feed on A. lusitanicum, A. minutum and A. tamarense strain AT-6, but could graze to little or no extent upon algal cells of the other seven strains. The effects on rotifers exposed to different cell densities, fractions, and growth phases of A. tamarense algal culture were respectively compared. It was found that only the whole algal cells had lethal effects, with strongest impact being shown by the early exponential growth phase of A. tamarense. The results indicate that some toxic mechanism(s), other than PSP and present in whole algal cells, might be responsible for the adverse effects on the exposed rotifers. (C) 2004 Elsevier B.V. All rights reserved.

General Harris regularity criterion for non-linear Markov branching processes

We extend the Harris regularity condition for ordinary Markov branching process to a more general case of non-linear Markov branching process. A regularity criterion which is very easy to check is obtained. In particular, we prove that a super-linear Markov branching process is regular if and only if the per capita offspring mean is less than or equal to I while a sub-linear Markov branching process is regular if the per capita offspring mean is finite. The Harris regularity condition then becomes a special case of our criterion.

Probabilistic approach in weighted Markov branching processes

This note provides a new probabilistic approach in discussing the weighted Markov branching process (WMBP) which is a natural generalisation of the ordinary Markov branching process. Using this approach, some important characteristics regarding the hitting times of such processes can be easily obtained. In particular, the closed forms for the mean extinction time and conditional mean extinction time are presented. The explosion behaviour of the process is investigated and the mean explosion time is derived. The mean global holding time and the mean total survival time are also obtained. The close link between these newly developed processes and the well-known compound Poisson processes is investigated. It is revealed that any weighted Markov branching process (WMBP) is a random time change of a compound Poisson process.